This invention relates to an anatomical model, particularly a dummy, for simulating the effect of an accident on the human body. The model is provided with a skeleton. In the area of the thorax, the skeleton is formed by several pairs of rib-curvature-type leaf springs which, as curved ribs, connect a backbone with a chestplate. The model is equipped with a mechanical-electrical transducer for the measuring of a mechanical quantity.
Occupants of passenger cars involved in accidents frequently suffer rib fractures that are caused by the impact of the upper body on the steering wheel or by an excessive straining of the thorax caused by the seat belt. As a result of these rib fractures, injuries to organs may occur that may be life-threatening.
In order to prevent, if possible, or at least reduce injuries of this type, an attempt is made to investigate the reasons for injuries of this type by means of anatomical models of the human body, so-called dummies, in crash tests. Although these dummies correspond largely to the human body with respect to weight, dimensions and structure, they must be constructed of unbreakable materials, so that they can be used repeatedly. As a result, no injuries can occur. However, in a crash test, mechanical quantities, such as force, accelerations or deformations, can be detected by measuring techniques which permit the drawing of conclusions concerning the extent of the strain on the corresponding part of the body.
Up to now, the dummy's thorax has been considered to be such a part where a measured maximum chest deformation of the dummy is used as a relevant criterion for the risk of injury to the thorax. However, this maximum chest deformation offers only vague clues for a real straining of the ribs because the impact surface and the direction of the blow are also of considerable importance. Thus, for example, the use of a thin nylon rope instead of a safety belt having the conventional width and having the conventional stretching capacity, despite identical chest deformation, resulted in a much higher risk of injury.
An object of this invention is to provide an anatomical model which supplies realistic information on the risk of injury to the human thorax as a result of accidents.
This object is achieved in accordance with a preferred embodiment of the invention by providing an anatomical model having a thorax area in which a plurality of spring rib members or leaf springs which simulate human ribs are disposed. Further, sensor means are provided on each spring rib member for sensing a force applied to each individual spring rib member. Using this arrangement, a deformation path of the spring rib members is transformed into a proportional electrical parameter. The stretching of the spring rib member in the measuring area can be measured and as a result permits exact conclusions concerning the partial stress at this measuring point. The total stressing of the thorax, including the spring rib members, can be obtained from the sum of the individual stresses to the spring rib members.
Further, for advantageously determining the proportions of the frontal and lateral stress to be determined as well, preferred embodiments of the invention provides the skeleton with a front chestplate member and a plurality of pairs of spring rib members disposed on opposite sides of the chestplate. At least one sensor means is provided on each of the spring rib members of each pair.
Other advantageous features are achieved in preferred embodiments in which the sensor means include a mechanical-electrical transducer for changing the deformation path of the spring rib members into a proportional electrical parameter.
Further advantageous features are achieved in preferred embodiments in which the sensor means is a measured value sensor and comprises a strain gauge.
Other advantageous features are achieved in preferred embodiments including a back plate to which the spring rib members are attached. In this preferred embodiment, the sensor means are attached near the back plate member.
Further objects, features, and advantages of the present invention will become more apparent from the following description when taken with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.